Pressure delay responsive device



Dec. 30, 1969 N. SCHWEIZER 3,487,185

PRESSURE DELAY RESPONSIVE DEVICE Filed Feb. 28, 1968 UDUDIJDDIJHDDDDDDDDD Fig. 2

INVENTOR.

NORMAN SCHWEIZER' BYW 71. W I 4. W M ATTO RNEYS United States Patent 3,487,185 PRESSURE DELAY RESPONSIVE DEVICE Norman Schweizer, 4916 Charles St., Philadelphia, Pa. 19124 Filed Feb. 28, 1968, Ser. No. 708,904 Int. Cl. H01h 35/38 US. Cl. 20082 6 Claims ABSTRACT OF THE DISCLOSURE A device for indicating the precise moment when the pressure rise within a pressure block begins utilizing the shorting of a circuit, of which the device is part, to cause a pulse to initiate a start and stop on a recording medium.

The invention described herein may be manufactured, used, and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

The present invention relates to a pressure delay, responsive, device and more particularly to a pressure delay, responsive, device for indicating the change of gas pressure within a pressure block.

In the past, the systems utilized for determining the pressure rise within a pressure block did not provide a means for determining the start of the rise. The technician could only guess as to the time when the rise occurred by picking an arbitrary point on the tracing and establishing that as the rise point. This method has proved to be inaccurate in that the points chosen did not necessarily constitute the actual point when the rise began.

It is therefore an object of the present invention to provide a pressure delay, responsive, device which would accurately indicate the precise moment that the pressure rise began.

The above object as well as others together with the benefits and advantages of the invention will be apparent upon reference to the detailed description set forth below, particularly when taken in conjunction with the drawings annexed hereio in which:

FIG. 1 shows a sectional side view of the invention.

FIG. 2 shows a tracing which is marked according to the invention.

Referring now to FIG. 1, there is shown a pressure delay, responsive, device which is inserted into the side of the test pressure block (not shown). The device 10 is comprised of a partially hollow cylinder or piston holder 12, having a multi-diameter bore axially through a solid portion 14 including a large diameter portion 16 and a small diameter portion 18. Integral with the solid portion 14 is a boss 20 for attaching said device to the test pressure block (not shown). A piston 22 is seated partially in the bore 16 and partially in the hollow portion 24 of the cylinder 12. When gas pressure is applied to the area of the boss 20 of the cylinder 12, the piston 22 is displaced a minute distance. A head portion 21 of the piston 22 manes contact with a contact shaft 26, having a round T-shaped head portion 27, and which extends through a nylon insulator 28 contained in a steel head casing 30. The extended part 32 of contact shaft 26 passes through an external reset spring 34 which is retained in position on the contact shaft 26 by a retainer washer 35 and an anvil spring retainer 36. Electrical contact is obtained by a lug type washer 38 located between the nylon insu- 3,487,185 Patented Dec. 30, 1969 lator 28 protruding above the steel head casing 30 and reset spring 34. A panel type connector 40, such as a B.N.C. connector, is mounted on the steel head casing 30 and connected to the lug washer 38. A plurality of seals 42 are provided to prevent any gas from prematurely leaking past the piston 22.

When the circuit is shorted by the piston 22 touching contact shaft 26, an external electronic source, whose input will respond to a shorting condition, will produce a pulse in its output. This output pulse caninitiate and terminate a start and stop indication on recording mediums such as Oscilloscopes, oscillogr aph, chronographs, and other types of electronic devices.

After the test is completed, the piston 22 is returned to its original postion by pushing on the anvil retainer 36, which causes the shaft 26 to move. The reset spring 34 then returns the shaft 26 back to its set position.

Referring now to FIG. 2, there is shown an actual tracing illustrating the pressure rise at a particular firing and it should be noted that the mark 44 illustrates the point at which the pressure begins to rise after the initiation of the firing. It should therefore be obvious that it is easy for the observer to note and measure from the point of pressure rise since it is indicated on the film itself.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

I claim:

1. A pressure delay, responsive, device including a partially hollow cylinder having a multi-diameter bore axially through its solid portion,

said multi-diam eter bore being of a larger diameter adjacent the hollow portion of said cylinder,

a boss integral with solid portion of saidcylinder having a bore axially aligned with the remaining smaller diameter portion of said bore of said cylinder,

a piston seated partially in said larger diameter portion of said bore and in said hollow portion of said cylinder,

a metallic head casing closing said hollow portion p rtion of said cylinder and having a bore therethrough in axial alignment with said piston,

a contact shaft secured in said casing bore,

insulator means separating said shaft from said casing,

electrical contact means on said shaft adjacent one end of said insulator means,

electrical connector means in contact with said contact means and supported by said metallic casing.

2. A device of the type as described in claim 1 wherein said contact shaft includes a rounded end portion in axial alignment with said portion.

3. A device of the type'as described in claim 2 wherein said insulator is made of nylon and is T-shaped to fit against said contact shaft.

4. A device of the type as described in claim 3 wherein said contact shaft passes through an external reset spring which is retained in position by an anvil spring retainer and a retainer washer.

5. A device of the type as described in claim 4 wherein said electric contact is a lug type washer located between the nylon insulator protruding above the head casing and reset spring.

3 4 6. A device of the type as described in claim 1 in- 3,098,209 7/1963 Stevens 338-39 eluding 3,172,974 3/1965 Perrino 200--82.3

a plurality of seals in postion between the piston and the small bore to prevent premature gas leakage past ROBERT K. SCHAEFER, Primary Examiner the piston. 5

References Cited 1. R. SCOTT, Asslstant Examlner UNITED STATES PATENTS US. Cl. X.R.

2,648,733 8/1953 Billings 20082.3 200-83 2,752,447 6/1956 Shaffer 20082.3 10 

